(1) Field of the Invention
The present invention relates to a hot-melt adhesive composition. More particularly, the present invention relates to a hot melt adhesive composition having an excellent adhesiveness even at a high temperature. Furthermore, the present invention relates to a sticking structure such as an adhesive tape or sticking label, formed by using this hot-melt adhesive composition.
(2) Description of the Related Art
An EVA type adhesive composition comprising polyvinyl acetate or an ethylene/vinyl acetate copolymer (EVA) as the base has been mainly used as the hot-melt adhesive for a label, a kraft tape, a cloth tape and the like.
Furthermore, a hot-melt adhesive composition comprising (a) a styrene/aliphatic diene block copolymer and (b) an alicyclic hydrocarbon resin tackifier is recently used.
The EVA type hot-melt adhesive composition is defective in that the adhesiveness to polyethylene, polypropylene, polyethylene terephthalate, urethane, ABS, polyvinyl chloride and 4-methylpentene-l polymer is low and the adhesiveness is drastically reduced at a high temperature.
The hot melt adhesive composition comprising a styrene/aliphatic diene block copolymer and an alicyclic hydrocarbon resin tackifier shows an excellent adhesiveness at a low temperature, but when the adhesive composition is used under heating or in an high-humidity atmosphere in hot water or in an electronic range, the adhesiveness is degraded.